I have an invisible enemy (an Oni).
The party's archer has just picked up a way to see invisible creatures.
He wants to use dye arrows to fire at the Oni and splash it with paint, which will then mark its location for everyone else.
Obviously the Oni can just use an action to become visible then go invisible again and turn the dye invisible – but until it does that, does this work? Does the dye get turned invisible even though it is applied after the invisibility is already active.
Best Answer
Yes, the target is made visible by the ink. From the Pathfinder Glossary entry on Invisibility:
Until the target casts Invisibility again, or takes some other action to remove the dye, they'll remain marked by it. As a fluid, the dye would also drip off the target and stain their feet, meaning that one could keep track of the invisible creature's footprints or the dripping of the dye to follow them.
Note that the rules for whether the dye will fade with a second cast of Invisibility aren't stated explicitly, it would be down to GM fiat. The rules of Invisibility seem to suggest that it would fade, as it's now being "carried" by the creature.
Hitting the creature with dye in the first place requires that you overcome or negate the concealment gained by Invisibility (50% miss chance). A creature covered with dye may also retain that concealment while "visible" (due to the dye not totally covering them), subject to GM discretion.